Together with the popular MARES Diving Center of IWM of Dieter Heinz in Antalya/Turkey we decided in 2006 to construct a simple diving bell for touristic purposes in a depth of appr. 9m. This diving bell would serve as an advertisement carrier, sales tool and later as a decompression stop bell if successfully positioned. It should last for at least two years being removed during six winter months. As a design we wanted the construction to follow the shape of a jelly fish and to look a bit futuristic. After agreeing and drawing the final design we calculated costs of 1000 € which included the umbrella, the skeleton, the counterweights and the working force.
For the umbrella we planned to use the spherical roof of mushroom-shaped playground contraption made of polyester with about 170 cm in diameter that would allow three divers to emerge inside comfortably. Filled with air it would generate a buoyancy of appr. 1280 kg. We ordered this part over a local playground company.
The skeleton was to be made of stainless chrome pipes and allow as much undivided space as possible inside the bell.
As counterweights we decided to use concrete wheels at the habitat itself to serve at the same time as a standing platform for the divers. Another one on the sea bottom would keep the habitat moored on position.
The habitat would be of yellow colour to be best visible at most conditions. Stabilization holes on the side above the skirt would maintain an upright position even at rough sea. Advertisements and warning symbols for snorkellers not to enter because the oxygen level might be too low had to be added.
After attaching the habitat to the counterweights underwater it was obvious that the skeleton would not be able to hold the habitat in shape. The used interior chrome pipes were just too weak. The photo below shows the shape change of the exterior chrome belts.
In the end we succeeded to moor the habitat on position as planned and to bring divers safely to the bell and back to the surface. Numerous divers had a good time with the habitat and for the Diving Center it was a great advertising tool.
It was actually not a big surprise that the chrome pipes would not hold the pocket of air. We reinforced the skeleton with three diagonal supports inside the bell (on the left side of the image below). But the ideal shape would probably have been the ‘apple shell’ (on the right side).
Another problem was the missing variable ballast. To remove the habitat it was necessary to detach the heavy concrete wheels. Unexpected bad weather and the shallow depth gave a bad damage to the habitat. Variable ballast, like easily removable sand, would have made us much more flexible in terms of removing the habitat. Additionally a greater depth would have decreased the risk of damage.
A considerable aspect of planning and building the habitat was the contribution to the team spirit. In 2006 the IWM team had several members and each of them had his part on the habitat. Though the project was semi-professional all team members remembered it for years.